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Abstract:

A stent loading and delivery system, the delivery system comprising an
inner elongate tubular member having a proximal end and a distal end, an
intermediate elongate tubular member having a proximal end and a distal
end in sliding relationship to said inner elongate tubular member and an
external elongate tubular member having a proximal end and a distal end
in sliding relationship to said intermediate elongate tubular member,
said intermediate elongate tubular member comprising a stop mechanism at
its proximal end, wherein the stop mechanism prevents the external
elongate tubular member from being slid past the stop mechanism when the
external elongate tubular member is slid in a proximal direction.

Claims:

1. A stent loading and delivery system, the delivery system comprising an
inner elongate tubular member having a proximal end and a distal end, an
intermediate elongate tubular member having a proximal end and a distal
end in sliding relationship to said inner elongate tubular member and an
external elongate tubular member having a proximal end and a distal end
in sliding relationship to said intermediate elongate tubular member,
said intermediate elongate tubular member comprising a stop mechanism at
its proximal end, wherein when the external elongate tubular member is
adjacent the stop mechanism, the external elongate tubular member does
not move in a proximal direction.

2. The stent loading and delivery device of claim 1 wherein the inner
elongate tubular member comprises a proximal handle at the proximal end,
the intermediate elongate tubular member comprises an intermediate handle
at the proximal end and the external elongate tubular member comprises a
distal handle at the proximal end, the distal handle has proximal
position and a distal position, when the distal handle is in the proximal
position, the external elongate tubular member overlies the stop
mechanism.

3. The stent loading and delivery device of claim 2, the stop mechanism
having an unexpanded and an expanded configuration, when the external
elongate tubular member overlies the stop mechanism the stop mechanism is
in its unexpanded configuration.

4. The stent loading and delivery device of claim 3 wherein when the
external elongate tubular member is in its distal position, the stop
mechanism is in its expanded configuration and when the distal handle of
the external elongate tubular member is adjacent the expanded stop
mechanism, the external elongate tubular member cannot be moved further
in a proximal direction.

5. The stent loading and delivery device of claim 1 further comprising a
stent loading basket, the stent loading basket is secured to the distal
end of the intermediate elongate tubular member.

6. The stent loading and delivery device of claim 5 in combination with a
stent having an unconstrained state and a constrained state and having a
proximal end and a distal end, the proximal end of the stent is disposed
within the stent loading basket.

7. The stent loading and delivery device of claim 6 wherein when the
external elongate tubular member is in the distal position the stent
loading basket and stent in a constrained state are within the distal end
of the external elongate tubular member

8. The stent loading and delivery device of claim 7 wherein when the
external elongate tubular member is adjacent the stop mechanism, the
stent is outside of the external elongate tubular member in an
unconstrained state and the stent loading basket is within the external
elongate tubular member.

9. The stop mechanism of claim 1 wherein the external elongate tubular
member has a distal end and a proximal end, the proximal end of the
external elongate tubular member has a proximal position and a distal
position, when the external elongate tubular member is in its proximal
position the external elongate tubular member overlies the stop mechanism
which is in a constrained state and when the external elongate tubular
member is in its distal position the stop mechanism is exposed in an
unconstrained state.

10. The stent loading and delivery device of claim 11 wherein the stop
mechanism has an unexpanded and an expanded state, the stop mechanism
forms a frustoconical cone in an expanded state.

11. The stent loading and delivery device of claim 1 wherein the stop
mechanism has an unexpanded and an expanded state and the stop mechanism
has a braided construction.

12. The stent loading and delivery device of claim 1 wherein the stop
mechanism comprises a compressible bump or sleeve on the intermediate
member.

13. A stent loading and delivery system comprising: an inner elongate
tubular member having a proximal end and a distal end, the inner elongate
tubular member having a proximal handle at the proximal end of the inner
elongate tubular member; an intermediate elongate tubular member in
sliding relationship with the inner elongate tubular member, the
intermediate elongate tubular member having a proximal end and a distal
end, the intermediate elongate tubular member having an intermediate
handle, the intermediate handle having a first position and a second
position, in the second position the intermediate handle is adjacent the
proximal handle; an external elongate tubular member having a proximal
end and a distal end, the external elongate tubular member overlying at
least a portion of the intermediate elongate tubular member and in
sliding relationship therewith, the external elongate tubular member
having a distal handle at the proximal end of the elongate external
tubular member, the distal handle having a proximal position and a distal
position; and a stop mechanism secured to the proximal end of the
intermediate elongate tubular member at a point corresponding to the
proximal position of the intermediate handle of the intermediate elongate
tubular member, the stop mechanism having a first unexpanded state and a
second expanded state; wherein when the distal handle of the external
elongate tubular member is in the first proximal position, the proximal
end of the external elongate tubular member overlies the stop mechanism
and the stop mechanism is in its unexpanded state and when the distal
handle of the external elongate tubular member is in the second distal
position, the stop mechanism is exposed and is in its expanded state, the
stop mechanism preventing the distal handle and external elongate tubular
member from moving to a point beyond the stop mechanism.

14. The stent loading and delivery system of claim 13 further comprising
a stent loading basket, the stent loading basket is secured to the distal
end of the intermediate elongate tubular member adjacent the distal end
of the external elongate tubular member.

15. The stent loading and delivery system of claim 12 in combination with
a stent, the stent having an unconstrained and a constrained state and a
distal end and a proximal end, the proximal end of the stent is disposed
within the stent loading basket in an unconstrained state when the distal
handle of the external elongate tubular member is in its proximal
position and when the handle of the external elongate tubular member is
in its distal position, the stent loading basket and the stent are in the
distal end of the external elongate tubular member.

16. The stent loading and delivery system of claim 15 wherein when the
distal handle of the external elongate tubular member is returned to the
proximal position adjacent the stop mechanism the stent is outside the
distal end of the external elongate tubular member in an unconstrained
state and the stent loading basket is within the distal end of the
external elongate tubular member in a constrained state.

17. The stent loading and delivery system of claim 13 wherein the stop
mechanism expands to form a frustoconical cone.

18. The stent loading and delivery system of claim 13 wherein the stop
mechanism comprises a pleated construction.

19. The stent loading and delivery system of claim 13 wherein the stop
mechanism comprises a flanged cone.

20. The stent loading and delivery system of claim 13 wherein the stop
mechanism comprises a braided construction.

21. The stent loading and delivery device of claim 13 wherein the stop
mechanism comprises a compressible bump or sleeve on the intermediate
member.

22. The stent loading and delivery system of claim 13 wherein the stop
mechanism is formed from at least one member selected from the group
consisting of polymers, flexible metals and shape memory metals.

23. A stent loading and delivery device comprising: at least one inner
tube having a proximal end and a distal end and a stop mechanism located
at the proximal end; and at least one outer tube having a proximal end
and a distal end, the outer tube in sliding relationship with said at
least one inner tube, the stop prevents the outer tube from advancing
proximally when the proximal end of the outer tube is adjacent the stop

[0002] The present invention relates to an assembly for loading and
delivering a stent.

[0003] An intraluminary prosthesis is a medical device used in the repair
and/or treatment of diseases in various body vessels, for example, a
stent. Stents are generally cylindrical shaped devices that are radially
expandable to hold open a segment of a blood vessel or other anatomical
lumen after implantation into the body lumen. For example, stents may be
used in the coronary or peripheral vasculature, esophagus, trachea,
bronchi colon, biliary tract, urinary tract, prostate, brain, as well as
in a variety of other applications in the body. These devices are
implanted within the vessel to open and/or reinforce collapsing or
partially occluded sections of the lumen.

[0004] Stents may be formed of metallic materials as well as polymeric and
biodegradable materials, either in total or in part. In many procedures,
polymeric or bioabsorbable prostheses are preferred over metallic
devices, for example, due to the relative ease of removing a device
intended for temporary implantation, or the capacity to be absorbed into
the body.

[0005] When maintained in the reduced-radius state under a constant load
for any appreciable length of time, a prosthesis formed of polymeric or
bioabsorbable material may, however, undergo permanent or plastic
deformation. When released from the catheter or other delivery device,
such prosthesis may radially self expand to a diameter considerably less
than its relaxed-state diameter prior to preloading. This phenomenon is
commonly referred to as stress relaxation or "creep". This phenomenon is
aggravated when a polymeric or bioabsorbable prosthesis is exposed to
elevated temperatures in its reduced-radius state, for example during a
sterilization procedure, which may be performed prior the outset of the
prosthesis deployment procedure.

[0006] To counteract this phenomenon of stress relaxation or creep, the
polymeric or bioabsorbable prosthesis may be sterilized and/or stored in
its relaxed state, i.e., not significantly reduced radial state, until
just before it is to be used. When the physician is about to begin a
procedure, he or she may load the polymeric prosthesis into the delivery
system. Consequently, the prosthesis remains compressed in the
reduced-radius state only for a short time, perhaps only several minutes.
While such a procedure counteracts the problem of creep, the procedure
is, however, more difficult and time consuming. Although it is common
practice to load a stent into a sheath during assembly of a stent
delivery system, such loading often involves numerous steps and often
requires the use of multiple components (e.g., tools and fixtures) that
are not part of the stent delivery system. For example, currently
available stent delivery systems often require that a stent be loaded
onto a delivery system by means of a funnel, basket or other similar
device which are not part of the delivery system.

[0007] There remains a need in the art for an improved stent loading
device that is permanently attached to a stent delivery system to allow
loading of a stent into stent delivery systems at the time of use, while
minimizing the risk of damaging the stent in the process.

SUMMARY OF THE INVENTION

[0008] The present invention is directed to a method and system for
delivering a self-expanding stent into a body lumen. In particular, the
present invention relates to an assembly and a method for loading and
delivering a stent in combination with a stent delivery catheter device,
as well as to overall stent delivery systems.

[0009] In one embodiment, the present invention relates to a stent loading
and delivery system, the delivery system including an inner elongate
tubular member having a proximal end and a distal end, an intermediate
elongate tubular member having a proximal end and a distal end in sliding
relationship to said inner elongate tubular member and an external
elongate tubular member having a proximal end and a distal end in sliding
relationship to said intermediate elongate tubular member, said
intermediate elongate tubular member comprising a stop mechanism at its
proximal end, wherein the stop mechanism prevents the external elongate
tubular member from being slid past the stop mechanism when the external
elongate tubular member is slid in a proximal direction.

[0010] In one embodiment, the present invention relates to a stent loading
and delivery system including an inner elongate tubular member having a
proximal end and a distal end, the inner elongate tubular member having a
proximal handle at the proximal end, an intermediate elongate tubular
member in sliding relationship to the inner elongate tubular member, the
intermediate elongate intermediate member having a proximal end and a
distal end, the intermediate elongate tubular member having an
intermediate handle, the intermediate handle having a first position and
a second position, in the second position the intermediate handle is
adjacent the proximal handle, an external elongate tubular member having
a proximal end and a distal end, the external elongate tubular member
overlying at least a portion of the intermediate elongate tubular member,
the external elongate tubular member having a distal handle at the
proximal end of the external elongate tubular member, the distal handle
having a proximal position and a distal position and a stop mechanism
secured to the proximal end of the elongate intermediate member at a
point corresponding to the proximal position of the distal handle of the
elongate external tubular member, the stop mechanism having a first
unexpanded state and a second expanded state wherein when the distal
handle of the external elongate tubular member is in the proximal
position, the proximal end of the external elongate tubular member
overlies the stop mechanism and the stop mechanism is in its unexpanded
state and when the distal handle of the external elongate tubular member
is in the second distal position the stop mechanism is exposed and is in
its expanded state, the stop mechanism preventing the distal handle from
moving to a point beyond the stop mechanism.

[0011] The device may further include a stent loading basket having
opposed proximal and distal ends. In some embodiments, the proximal end
may be securely disposed to the distal end of the intermediate elongate
tubular member. The stent basket may have a truncated-conical shape,
outwardly diverging in a distal direction from its proximal end. The
stent basket may be a thin film which can collapse such that the stent
basket may be slidably contained within the external member, or may be a
radially distensible member which can collapse such that the stent basket
may be slidably contained within the external member. In some
embodiments, the stent basket may be composed of a polymeric material.
The stent basket may include, in part or substantially, braided polymeric
filaments. The braided filaments may be contained within a thin polymeric
film. The intermediate member may be an elongate tubular device. The
stent basket may comprise metals, polymers, or combinations of both.

[0012] In another embodiment, the present invention relates to A stent
loading and delivery device including at least one inner tube having a
proximal end and a distal end and a stop mechanism located at the
proximal end and at least one outer tube having a proximal end and a
distal end, the outer tube in sliding relationship with said at least one
inner tube, the stop prevents the outer tube from advancing proximally
when the proximal end of the outer tube is adjacent the stop.

[0013] The method of utilizing the system for stent loading and delivery
is also contemplated herein.

[0014] These and other aspects, embodiments and advantages of the present
disclosure will become immediately apparent to those of ordinary skill in
the art upon review of the Detailed Description and Claims to follow.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015]FIG. 1 is a side view of an embodiment of a stent loading and
delivery device according to the invention prior to stent loading.

[0016]FIG. 2 is a side view of an embodiment of a stent loading and
delivery device similar to that shown in FIG. 1 wherein the stent and
stent loading basket have been loaded into the distal end of the external
elongate tubular member.

[0017]FIG. 3 is a side view of an embodiment of a stent loading and
delivery device similar to that shown in FIGS. 1 and 2 wherein the stent
has been deployed and the stent loading basket remains in the distal end
of the external elongate tubular member.

[0018]FIG. 4 is an embodiment of a stop mechanism according to the
invention.

[0019] FIG. 5A is an alternative embodiment of a stop mechanism according
to the invention prior to expansion.

[0020]FIG. 5B is an embodiment of a stop mechanism similar to that shown
in FIG. 5A in an expanded state.

[0021] FIG. 6A is an alterative embodiment of a stop mechanism according
to the invention in an unexpanded state.

[0022]FIG. 6B is an embodiment of a stop mechanism similar to that shown
in FIG. 6A in an expanded state.

[0023] FIG. 6C is an embodiment of a stop mechanism similar to that shown
in FIGS. 6A and 6B in an expanded state with the distal handle of the
external elongate tubular member adjacent thereto.

[0024]FIG. 7 is a partial view of an intermediate member showing an
alternative embodiment of a stop mechanism in the form of a compressible
bump.

[0025]FIG. 8A is partial view of an intermediate member showing an
alternative embodiment of a stop mechanism in an unexpanded state wherein
stop mechanism is disposed on the intermediate member and in the handle
portion.

[0026]FIG. 8B is a partial view of an intermediate member showing a stop
mechanism similar to that shown in FIG. 8A in an expanded state.

DETAILED DESCRIPTION OF THE INVENTION

[0027] While embodiments of the present disclosure may take many forms,
there are described in detail herein specific embodiments of the present
disclosure. This description is an exemplification of the principles of
the present disclosure and is not intended to limit the disclosure to the
particular embodiments illustrated.

[0028] As shown in the drawings and described throughout the following
description, as is traditional when referring to relative positioning on
an object, the term "proximal" refers to the end of the apparatus that is
closer to the user and the term "distal" refers to the end of the
apparatus that is further from the user. The distal end in the operative
position is located within the patient's body and the proximal end in the
operative position is located outside the patient's body.

[0029] The present application is directed to stent loading and delivery
device including an inner elongate tubular member, an intermediate
elongate tubular member having a stop mechanism located on its proximal
end and an external elongate tubular member. The system may further
include a stent loading basket wherein the proximal end of a stent is
disposed and held therein in an expanded or non-contracted state. The
stent loading basket and stent can be loaded into the external elongate
tubular member between the external member and the inner elongate tubular
member and is held adjacent to the loading basket but no longer disposed
therein. When the stent is deployed using the external elongate tubular
member, a stop mechanism incorporated with the intermediate elongate
tubular member prevents the loading basket from being deployed from
within the external elongate tubular member. The device will be described
in detail with respect to the drawings below.

[0030] The method of utilizing the stent loading and delivery device is
also contemplated by the present invention. In some embodiments, the
utilization may include a method for loading, delivery and deployment of
a stent utilizing the system in percutaneous, transluminal or other
insertion techniques. The device allows the practitioner to easily load a
stent into the delivery system with minimal effort and without damaging
the stent.

[0031] Turning now to the figures, FIG. 1 is a cross-sectional view of a
stent loading and delivery system 100 according to the present invention.
The system 100, as depicted, may be particularly well suited for loading,
transluminal delivery and intraluminal deployment of a radially
self-expanding prosthesis, such as a stent and/or a stent-graft. The
system 100 may include a catheter-type device with three elongated
cylindrical members concentric about an axis and having opposed proximal
and distal ends. The three members can be structured as follows: A
flexible inner elongate tubular member 120, an intermediate elongate
tubular member 140 slidably containing the inner member 120 therein, and
an external elongate tubular member 160 slidably containing the
intermediate member 140 therein.

[0032] Stent loading basket 200 is secured to the distal end of the
intermediate member and lies adjacent the distal end of the external
member and holds stent 300 in an unconstrained state therein.

[0033] Each member 120, 140, 160 of the system 100 may be controlled at
the proximal end by a respective handle as follows. A proximal handle 130
may be fixedly disposed at the proximal end 117 of the inner member 120,
handle 150 may be disposed at the proximal end 137 of the intermediate
member 140 and handle 170 may be disposed at the proximal end 157 of the
external member 160. Handle 170 is shown disposed furthest away from the
practitioner in relation to other handles or away from the proximal end
117 of the inner member 120 in this embodiment. The intermediate handle
150 may be disposed between the distal handle 170 and the proximal handle
130, which may be disposed closest to the practitioner.

[0034] Handles 130, 150, and 170 are displaceable along the longitudinal
axis 98 relative to each other thereby enabling selective deployment and
retraction of the stent 300. Manipulation or axial movement of the
handles 130, 150 and 170 permits independent axial movement of the
tubular members 120, 140, and 160, respectively. For example, handle 150
may slide between a distal position 151 shown in FIG. 1 and a proximal
position 153 shown in FIG. 2 so as to axially move the intermediate
member 140. Such movement may be done while keeping the other handles
130, 170 fixed or relatively fixed to allow independent or substantially
independent movement of the intermediate member 140. While the
intermediate member 140 is moved, the inner member 120 and the external
member 160 may remain fixed or relatively fixed.

[0035] Handle 170 is fixedly attached to the distal end 157 of external
member 160 and moves proximally and distally between first and second
positions 171 (proximal), 173 (distal).

[0036] When handle 170 is moved from proximal position 171 to distal
position 173 stent loading basket 200 which engages and secures a
proximal end of stent 300 is compressingly loaded along with stent 300
into the distal end 161 of the external tubular member 160 and holds the
stent in a collapsed and constrained position over the inner tubular
member 120 as shown in FIG. 2.

[0037] The intermediate handle 150 is moved from a distal position shown
at 151 in FIG. 1 to a proximal position 153 adjacent handle 130 as shown
in FIG. 2. This seats the stent 300 immediately adjacent stent loading
basket 200 with the proximal end of the stent 300 no longer within
loading basket 200 as shown in FIG. 2.

[0038] During the loading of the stent 300, the handles 170 and 150 may be
kept fixed in relatively constant axial displacement from one and
another. As such, the inner member 120 and the intermediate member 140
may also be kept in relative constant axial positions with the
intermediate member 140 being substantially disposed within the external
member 160. However, the intermediate member 140 need not be completely
contained within the external member 160. Rather, a portion of the distal
end of the intermediate member 140 may be axially outside or distally
disposed from the distal end of the external member 160.

[0039] An added feature may be a stent holder (not shown) which can be
provided on a distal portion referred to as the stent engagement region
110 of the inner elongate tubular member 120 to temporarily hold the
stent in place without any substantial external force acting on it. The
stent holder may be further defined by a tubular band (not shown). The
stent holder may releasably hold stent 300 within system 100 even after
the stent basket 200 may be axially displaced away from the stent 300.
Such feature may allow, if desired, for a large portion of the stent 300
to be deployed and then be recaptured or re-engaged by stent basket 200
prior to complete deployment of the stent 300. The recapturing may be
achieved by axially sliding the external member 160 over the stent 300.
Moreover, the stent basket 200 may be repositioned between the inner
member 120 and the external member 160, for example, by axially advancing
the stent basket 200 to reposition the stent 300 therein between.
Furthermore, the whole system 100 may be moved proximally or distally to
reposition the stent 300 therein. These features may provide, among other
things, reloading ability (reconstrainability) of the stent 300 within
the system 100 of the present invention. These features are described
more fully in US Patent Publication No. 2009/0192518.

[0040] Thus, during delivery through a patient's body lumen, the stent 300
is releasably secured in the stent deployment region 110 between the
inner and outer tubular members 120, 160.

[0041] The stent delivery system 100 can now be positioned in the patient
for deployment of stent 300. Insertion of the distal end of the system
100 into a patient's body is performed with a lead-in such as the distal
end tip 240. Once the practitioner navigates the distal end tip 240 to a
desired location, and is satisfied with the location and orientation of
the partially deployed stent 300, the practitioner can actuate the handle
170 to its proximal position 171 to release fully deploy the stent 300
from the deployment region 110 of the delivery system. as depicted in
FIG. 3. The practitioner can then pull back the distal handle 170 toward
the intermediate handle 150, thereby pulling back the external member
160. This step uncovers the constrained stent 300 can be unloaded at the
desired deployment site. The delivery system 100 can then be removed from
the body.

[0042] It should be noted that the stent loading and delivery device can
be configured and arranged to allow a practitioner to re-load the stent
in the event that it is positioned at the wrong location within a
patient. For example, the intermediate handle 150 may have a release
mechanism such that the intermediate handle 150 can be repositioned back
to the original position if the stent 300 needs to be removed from the
body and re-loaded. Optionally, the system can be positioned by axially
moving or sliding the stent engaging basket 200 to a location past the
stent deployment region 110 for disengagement of the stent 300 from the
intermediate member 140.

[0043] A device of this type can be found in US Patent Publication No.
2009/0192518, the entire content of which is incorporated by reference
herein.

[0044] A stop mechanism 180 is located at and secured to the proximal end
of the intermediate member 140 which corresponds to position 171 of
handle 170. When handle is at position 170 the external member 160
constrains the stop mechanism in a first collapsed position. As shown in
FIGS. 2 and 3, when the handle 170 is moved distally to position 173 the
stop mechanism expands to form a conical flare at one end. When the
handle 170 is moved back to position 171 after stent deployment, the stop
mechanism prevents the external member 160 from being retracted any
further and deploying stent loading basket 200 from the distal end 161 of
the external elongate tubular member. This prevents the catheter assembly
from being reused for future procedures.

[0045] One embodiment of a stop mechanism 180 is shown in FIG. 4. In this
embodiment, the distal end of the stop mechanism comprises flanges 210
which expand outwardly once the handle 170 is moved in a distal direction
to position 173.

[0046] An alternative stop mechanism 180 is shown in FIG. 5A (unexpanded
state) and FIG. 5B (expanded state). The stop mechanism 180 is shown in
the shape of a frustoconical cone having tabs or pleats 190 formed
therein.

[0047] Yet another alternative design can be found in FIG. 6A (unexpanded
state), FIG. 6B (expanded state), and FIG. 6C (shown secured to the
intermediate elongate tubular member 140 and adjacent to the distal
handle 170 of the elongate external tubular member 160 when the distal
handle 170 is in its proximal position again after stent deployment).
This stops the external elongate tubular member 160 from being moved any
further proximally and prevents the loading basket 200 from being
deployed from within the distal end 161 of the elongate external tubular
member 160 (also shown in FIG. 3). The stop mechanism 180 depicted in
FIGS. 6A-6C is in the form of a tubular braid, much like a braided stent.

[0048] In any of the above embodiments, the tubular members 120, 140, and
160 may be formed of a biocompatible material such as a biocompatible
polymer.

[0050] It should be noted that the stop mechanism 180, while shown as
having a conical flare when expanded, can be anything that is covered by
the external handle 160 upon loading, but is exposed when the handle 160
is moved distally. The form of the stop mechanism 180 may include, but is
not limited to, a compressible bump, a raised portion on the intermediate
member 140, a leaf spring, etc.

[0051]FIG. 7 is a partial view of intermediate member 140 illustrating an
alternative embodiment wherein the stop mechanism 180 is in the form of a
compressible bump or sleeve on the intermediate member 140.

[0052] FIGS. 8A and 8B illustrate yet another alternative embodiment
wherein stop 180 is both disposed on the intermediate member 140 and in
handle portion 170. FIG. 8A illustrates stop mechanism 180 in an
unexpanded state and FIG. 8B illustrates stop mechanism 180 in an
expanded state both within handle 170 and on intermediate member 140.

[0053] Alternatively, the stop may be included on the handle portion 170
that prevents proximal movement beyond the point shown in FIG. 3.

[0054] The tubular members 120, 140, and 160 may also have a surface
treatment and/or coating on their inner surface, outer surface or
portions thereof. A coating need not be applied to all of the tubular
members 120, 140, 160, and individual members may be coated, uncoated,
partially coated, and the like. Useful coating materials may include any
suitable biocompatible coating. Non-limiting examples of suitable
coatings include, but are not limited to, polytetrafluoroethylene,
silicone, hydrophilic materials, hydrogels, and the like. Useful
hydrophilic coating materials include, but are not limited to, alkylene
glycols, alkoxy polyalkylene glycols such as methoxypolyethylene oxide,
polyoxyalkylene glycols such as polyethylene oxide, polyethylene
oxide/polypropylene oxide copolymers, polyalkylene oxide-modified
polydimethylsiloxanes, polyphosphazenes, poly(2-ethyl-2-oxazoline),
homopolymers and copolymers of (meth)acrylic acid, poly(acrylic acid),
copolymers of maleic anhydride including copolymers of methylvinyl ether
and maleic acid, pyrrolidones including
poly(vinylpyrrolidone)homopolymers and copolymers of vinyl pyrrolidone,
poly(vinylsulfonic acid), acryl amides including poly(N-alkylacrylamide),
poly(vinyl alcohol), poly(ethyleneimine), polyamides, poly(carboxylic
acids), methyl cellulose, carboxymethylcellulose, hydroxypropyl
cellulose, polyvinylsulfonic acid, water soluble nylons, heparin,
dextran, modified dextran, hydroxylated chitin, chondroitin sulphate,
lecithin, hyaluranon, combinations and copolymers thereof, and the like.
Non-limiting examples of suitable hydrogel coatings include polyethylene
oxide and its copolymers, polyvinylpyrrolidone and its derivatives;
hydroxyethylacrylates or hydroxyethyl(meth)acrylates; polyacrylic acids;
polyacrylamides; polyethylene maleic anhydride, combinations and
copolymers thereof, and the like. Additional details of suitable coating
materials and methods of coating medical devices with the same among
other features may be found in U.S. Pat. Nos. 6,447,835 and 6,890,348,
the contents of which are incorporated herein by reference. Such coatings
and/or surface treatment can be desirably disposed on the inside or a
portion thereof of the external member 160 to aid, if desired, in loading
and/or deploying of the stent.

[0055] The stent basket 200 may have a truncated-conical shape, being
smaller at its proximal end, i.e., outwardly diverging in a distal
direction from its proximal engaging end. The stent basket 200 may be a
thin film which can collapse such that the stent basket 200 may be
slidably contained within the distal end of the external member 160.
Alternatively, the stent basket 200 may include a radially distensible
member which can be collapsible such that the stent basket 200 can be
slidably contained within the external member 160. For instance, the
stent basket may be a porous tube, a flexible tube, or any other
configurable tube. In some embodiments, the stent basket 200 may be a
polymeric member 200. The stent basket 200 may include, in part or
substantially, braided filaments 206. The braided filaments 206 may
include polymeric filaments, metallic filaments and any other suitable
filaments. Alternatively, the braided filaments may be contained within a
thin polymeric film.

[0056] The stop mechanism can be formed from any of a variety of flexible
materials including polymer materials, flexible metals and shape memory
metals, and may be the same as or different than the intermediate
elongate tubular member to which it is attached.

[0057] The stop mechanism is suitably integrated with the intermediate
elongate tubular member using any suitable means known in the art such as
by overmolding or applying heat to the interface once the stop mechanism
is disposed on the intermediate elongate tubular member such as by
welding or applying a laser.

[0058] Examples of flexible metals for forming the stop mechanism include,
but are not limited to, stainless steel, aluminum and copper, for
example.

[0059] Examples of polymer materials suitable for forming the stop
mechanism include, but are not limited to, polyurethanes, polycarbonate
and polyesters, for example. Elastomeric polymer materials being
preferred.

[0060] Examples of shape memory metals suitable for forming the stop
mechanism include, but are not limited to, copper-zinc-aluminum-nickel,
copper-aluminum-nickel, and nickel-titanium (NiTi) alloys, and can be
formed from alloying zinc, copper, gold and iron. Nickel-titanium is a
preferred shape memory metal.

[0061] Monofilaments available in a variety of polymeric materials
including nylon, polyethylene (UHMW), liquid crystal polymers, aramids
such as para-aramid, etc. can also be employed herein such as for making
a braided stop. Flexible metals and shape memory metals can also be
employed in making a web or braid.

[0062] The device according to the invention is particularly suited for
the loading and delivery of stents and stent/grafts.

[0064] A particular example of a non-vascular application is for
maintaining esophageal luminal patency in esophageal structures and
occlusions of the concurrent esophageal fistulas.

[0065] Examples of esophageal stents which can be employed herein include,
but are not limited to, the Polyflex® Esophageal Stent, a polyester
silicone-covered stent, the WallFlex® stent. WallStent®, and the
Ultraflex® stent which is a polyurethane covered Nitinol stent, all
commercially available from Boston Scientific/Microvasive, in Natick,
Mass.

[0066] Stents sold under these tradenames and available from Boston
Scientific are also available for use in the tracheobronchial system, the
biliary tract the duodenum and the colon, for example, and can also be
used with these loading and delivery systems.

[0068] The description provided herein is not to be limited in scope by
the specific embodiments described which are intended as single
illustrations of individual aspects of certain embodiments. The methods,
compositions and devices described herein can comprise any feature
described herein either alone or in combination with any other feature(s)
described herein. Indeed, various modifications, in addition to those
shown and described herein, will become apparent to those skilled in the
art from the foregoing description and accompanying drawings using no
more than routine experimentation. Such modifications and equivalents are
intended to fall within the scope of the appended claims.

[0069] All publications, patents and patent applications mentioned in this
specification are herein incorporated by reference in their entirety into
the specification to the same extent as if each individual publication,
patent or patent application was specifically and individually indicated
to be incorporated herein by reference. Citation or discussion of a
reference herein shall not be construed as an admission that such is
prior art.

Patent applications by Andrew Hollett, Waltham, MA US

Patent applications by Eric M. Schneider, Lincoln, RI US

Patent applications by BOSTON SCIENTIFIC SCIMED, INC.

Patent applications in class Expandable stent with constraining means

Patent applications in all subclasses Expandable stent with constraining means